I created a DotNetOpenAuth MVC 2 project using the visual studio template, and have it working. However, the sign in page takes a long time to load. Not quite sure exactly what is going on in the library, but it seems like there is some kind of javascript slowing down the login image button UI from rendering quickly.
I'd like to instead use the openid-selector on the client, rather than the MVC helpers from the DotNetOpenAuth library. What kinds of client & server hooks is the HtmlHelper in this example hiding?
The openid-selector client, if you're talking about the one like StackOverflow uses, has no server-side hooks at all in the same way that the HtmlHelper's in DNOA use, since the openid-selector makes no AJAX calls back to the server. DNOA's selector control uses AJAX a lot to provide users with an auto-login experience, auto-discovery as they type in the identifier, etc.
So in short, yes, the openid-selector (SO-style) is much simpler and works great with DNOA as well.
And yes, DNOA's built-in AJAX selector loads more slowly. That's something that I (or a volunteer) still need to work on speeding up.